The present invention relates to lift trucks and the like constructed to select elongated product from storage shelves/racks, and more particularly relates to a lift device where a worker rides with a platform to pick elongated product (i.e. especially product which is too long to easily hold and/or carry, such as 20 foot steel pipe of 20-50 lbs.) from elevated storage shelves/racks, transporting the selected/picked product back to ground level.
A number of lift devices are known. Side loaders (see FIGS. 11-12) are configured to lift a storage unit to a height where elongated product can be picked and set on the storage unit, and afterwards lowering the storage unit to a ground level. However, as shown in FIGS. 11-12, the operator and controls remain at ground level. This results in a circumstance where a second worker must climb the shelves/racks to pick product and put it on the storage unit. It is arguably unsafe for a worker to climb around to different levels on the storage racks. It is quite unsafe for a single worker to try to control the lift and also climb around racks to pick product, since they would have to climb around on the side loader and on the shelves/racks.
Fork lifts (FIGS. 13-14) can also be used. However, they include forks that extend away from the operator, such that they require a wide aisle. Further, a second worker must climb the shelves/racks to pick product and put it on the storage unit, which is unsafe as noted above. Like side loaders, it is quite unsafe for a single worker to try to control both a fork lift and also pick product, since they have to climb around on the fork truck and on the shelves/racks. Even with “4 directional” fork trucks, where the fork truck is adapted to move fore-aft as well as laterally, a very wide aisle is required due to a length of the fork truck and horizontally-extending forks. A wide aisle leads to excessively large storage areas and widely-spaced-apart storage racks, which adds considerably to overhead costs and poor retrieval time efficiency.
Order pickers (FIGS. 15-17) are lifts where the operator and controls move with a platform. The operator rides the platform, and can turn 90 degrees to pick product, resting the picked product on the platform adjacent his position. However, this does not work for elongated product (especially product that is 20 feet or longer), since elongated product can't easily be rotated 90 degrees due to its length, nor can it be “tucked” between the operator's feet. Also, the elongated product cannot be safely stored at an outer edge of the platform, since this would result in an unsafe and unbalanced position potentially tending to cause the order picker to tip toward the shelves/racks from which product is being picked. Also, the picked elongated product is often somewhat heavy (e.g. 20-50 lbs or more), which elongated product is unstable on a (narrow) platform of a typical order picker. This potentially creates a fall hazard which can hurt people below and also damage picked product that falls to the ground in the process. Also, a combined weight of the elongated picked product quickly adds up to an unacceptably heavy load that is unbalanced (in both fore-aft and side-to-side directions) and hence it cannot be stored at outer edges of the truck's forks, especially when the fork truck is being operated in raising and lowering operations.
A lift apparatus is desired that is particularly adapted for picking from high shelves/racks (such as 8-20 feet high) selected elongated product (such as 10-20 feet long) having significant weight (such as 10-20 lbs. or often 40-50 lbs. or more). Also, a lift apparatus is desired that is particularly adapted to retrieve elongated product, safely store and carry it to the ground, as well as to facilitate restocking of elongated product onto storage shelves/racks.